1. Field of the Invention
This invention relates to novel syringes and catheters for delivering compositions which form solid masses in vivo. These syringes and catheters are particularly useful for delivering embolizing compositions in situ (e.g., intravascularly).
2. State of the Art
The delivery of fluid compositions which solidify in vivo is particularly useful for a variety of reasons including embolization of blood vessels in the treatment of tumors, aneurysms, arteriovenous malformations (xe2x80x9cAVMsxe2x80x9d), arteriovenous fistula (xe2x80x9cAVFxe2x80x9d), uncontrolled bleeding and the like, as well as in the sterilization of mammals by blocking the vas deferens or fallopian tubes, in the treatment of urinary incontinence by the addition of a bulking agent to the periurethral tissue and the like.
Delivery of such compositions is preferably accomplished via catheter techniques which permit the selective placement of the catheter at the delivery site. For example, recent advancements in catheter technology as well as in angiography now permit neuro endovascular intervention including the treatment of otherwise inoperable lesions. Specifically, development of microcatheters and guide wires capable of providing access to vessels as small as 1 millimeter in diameter allows for the endovascular treatment of many lesions.
Catheter delivery for in vivo solid mass formation can employ fluid compositions which comprise a solvent such as ethanol, dimethylsulfoxide (xe2x80x9cDMSOxe2x80x9d), or aqueous solutions of ethanol or DMSO, a biocompatible water insoluble polymer, and a water insoluble contrast agent. Preferably, however, the solvent is non-aqueous in order to maximize the amount of biocompatible water insoluble polymer which can be dissolved therein.
In practice, the catheter tip is directed to the vascular or other delivery site by use of an aqueous solution containing an aqueous based contrast agent which permits the physician to visualize the catheter tip under conventional techniques such as fluoroscopy, and the like. After placement of the catheter, the composition is introduced into the catheter and delivered to this site. Upon delivery, the solvent dissipates into the blood, fluid or tissue and the water insoluble polymer and contrast agent precipitate to form a coherent mass which solidifies in vivo.
In embolic procedures, for example, the solvent is selected to be miscible or soluble in blood or other body fluid and to solubilize the water insoluble biocompatible polymer during delivery. The biocompatible polymer is selected to be soluble in the solvent but insoluble in blood or other body fluid. The contrast agent is suspended in the composition to provide for a deliverable fluid and, as above, is selected to permit the physician to fluoroscopically or otherwise visualize catheter delivery of this composition. Upon contact with the blood or other body fluid, the solvent dissipates from the composition whereupon the biocompatible polymer precipitates in the presence of the water insoluble contrast agent and, in the case of delivery to blood vessels, embolizes the blood vessel.
A problem may arise, however, when this composition is injected at the delivery site after delivery of an aqueous solution such as an aqueous solution containing a contrast agent. Specifically, it has been found that the catheter line can become plugged due to premature precipitation of the biocompatible polymer which plugging, of course, interferes with delivery of the composition to the specific site in vivo.
This invention, generally speaking, provides syringes and catheters which inhibit premature precipitation of fluid compositions which form solid masses in vivo.
This invention provides novel syringes particularly useful for avoiding premature precipitation of a fluid composition designed to form a solid mass in vivo. This invention also provides novel catheters for delivering such compositions to in vivo sites. In a preferred embodiment, the syringe is used in combination with the novel catheter for use in methods of in vivo embolization of blood vessels.
In one aspect, this invention addresses the problem of premature precipitation of a biocompatible polymer in a fluid composition designed to form a solid mass in vivo by providing for a novel syringe which syringe comprises:
(a) a body for holding a fluid composition;
(b) an ejection port having an annular wall and an orifice therethrough which extends from the syringe body to a distal end of said port wherein said annular wall is tapered at the distal end along the length of at least a portion of the ejection port;
(c) a means for ejecting the fluid composition out of the syringe, and
(d) a means for mating the syringe body to a catheter luer hub.
In a preferred aspect of the invention, the syringe is mated with a microcatheter luer hub.
In another aspect, this invention addresses the problem of premature precipitation of a biocompatible polymer in a fluid composition by providing for a catheter comprising (a) a luer hub body for holding a fluid composition and a delivery means attached to luer hub body wherein the luer hub body has a maximal volumetric capacity of no more than 0.2 cc, and (b) at least one means for mating the luer hub body to a syringe.
In one of its method aspects, this invention provides a method for inhibiting premature precipitation of a biocompatible polymer of a fluid composition designed to form a solid mass in vivo which composition is delivered by a microcatheter to a vascular site of a mammal where it precipitates and embolizes the vascular site. In this method, the composition is selected and placed into a syringe. The syringe comprises:
(a) a syringe body for holding a fluid composition,
(b) an ejection port having an annular wall and an orifice which extends from the syringe body to a distal end of said port wherein said annular wall is tapered at the distal end along the length of at least a portion of the ejection port,
(c) a means for ejecting the fluid composition in the syringe body through the ejection port and out of the syringe; and
(d) a means for mating said syringe body to a catheter luer hub.
A catheter tip of a microcatheter is then directed to a vascular site by use of an aqueous solution containing an aqueous based contrast agent and the syringe is then mated to a microcatheter luer hub. The fluid composition is injected into the microcatheter and then into the vascular site under conditions which embolize the vascular site.
In another of its method aspects, this invention provides a method for inhibiting premature precipitation of a biocompatible polymer in a fluid composition designed to form a solid mass in vivo which composition is delivered by a microcatheter to a vascular site of a mammal where it precipitates and embolizes the vascular site. In this method, the composition is selected and placed into a syringe. The syringe comprises:
(a) a syringe body for holding a fluid composition,
(b) an ejection port,
(c) a means for ejecting the fluid composition in the syringe body through the ejection port and out of the syringe; and
(d) a means for mating said syringe body to a catheter luer hub.
A catheter tip of a microcatheter is then directed to a vascular site by use of an aqueous solution containing an aqueous based contrast agent and the syringe is then mated to a microcatheter luer hub comprising:
(a) a luer hub body for holding a fluid composition and a catheter delivery line attached to the luer hub body wherein the luer hub body has a maximal volumetric capacity such that the amount of solvent mixing is reduced when the fluid composition in injected therein in the presence of a residual aqueous solution, and
(b) at least one means for mating the luer hub body to a syringe. The fluid composition is injected into the microcatheter and then into the vascular site under conditions which embolize the vascular site.
Preferably, the luer hub body has a maximal volumetric capacity of no more than 0.2 cc.
Preferably, the novel luer hub defined herein is used in combination with the novel syringe also defined herein.
In a preferred embodiment, this invention provides for a syringe/catheter combination comprising:
(a) a catheter comprising a luer hub for holding a fluid composition and a delivery means attached to luer hub body, and at least one means for mating the luer hub body to a syringe,
(b) a syringe comprising a syringe body for holding a fluid composition, an ejection port, a means for ejecting the fluid composition out of the syringe, and a means for mating the syringe body to a catheter luer hub such that the dead space arising from mating said syringe body to said catheter is reduced.
The invention further provides a kit of parts comprising:
(1) a syringe which comprises: (a) a syringe body for holding a fluid composition, (b) an ejection port having an annular wall and an orifice which extends from the syringe body to a distal end of said port wherein said annular wall is tapered at the distal end along the length of at least a portion of the ejection port, (c) a means for ejecting the fluid composition in the syringe body through the ejection port and out of the syringe, and (d) a means for mating said syringe body to a catheter luer hub; and
(2) a microcatheter luer hub which mates to the syringe.
In a preferred aspect, the kit of parts also includes a composition comprising (a) a biocompatible polymer; (b) a contrast agent; and (c) a biocompatible solvent.
In another preferred aspect, the microcatheter luer hub employed in this kit comprises (a) a luer hub body for holding a fluid composition and a catheter delivery line attached to luer hub body wherein the luer hub body has a maximal volumetric capacity such that the amount of solvent mixing is reduced when the fluid composition in injected therein in the presence of a residual aqueous solution, and , and (b) at least one means for mating the luer hub body to a syringe.